Muffler for boats



FIG. 1 is a perspective view of a muffler for boats showing my new design; the broken-line showing of the boat hull being for illustrative purposes only and forming no part of the claimed design;

FIG. 2 is an enlarged end elevational view thereof;

FIG. 3 is an enlarged bottom plan view thereof;

FIG. 4 is an enlarged right side elevational view thereof;

FIG. 5 is an enlarged left side elevational view thereof;

FIG. 6 is an enlarged top plan view thereof; and

FIG. 7 is a side elevational view taken in the direction of line 7--7 of FIG. 2. 

The ornamental design for a muffler for boats, as shown and described. 